Surfer contains filtering commands which operate on grid files, or on contours in a contour map. These commands round out angular contours, eliminate noise in a map, or change the density of a grid.
These are the smoothing methods available in Surfer:
Filter contains predefined filtering options and also allows you to define your own filtering schemes.
Spline Smooth is best for eliminating angular contours or surfaces; this operation fills in a sparse grid. For example, a 10 x 10 grid might result in very angular contours on a contour map produced from the grid. By increasing the grid density using the Grids | Edit | Spline Smooth command, the 10 x 10 grid can be expanded to a 50 x 50 grid. The 50 x 50 grid produces a much smoother appearing contour map than the 10 x 10 grid.
The Smooth tool in the Grid Editor smooths the grid with a 3x3 averaging filter.
Contour Smoothing smooths contour lines of a contour map by smoothing the grid file or changing the contour map properties.
Filter Data Before Gridding
To filter your data before gridding, use the data filters in Grids | New Grid | Grid Data.